debugfs/do_journal.c

   1 /*
   2  * do_journal.c --- Scribble onto the journal!
   3  *
   4  * Copyright (C) 2014 Oracle.  This file may be redistributed
   5  * under the terms of the GNU Public License.
   6  */
   7
   8 #include "config.h"
   9 #include <stdio.h>
  10 #ifdef HAVE_GETOPT_H
  11 #include <getopt.h>
  12 #else
  13 extern int optind;
  14 extern char *optarg;
  15 #endif
  16 #include <ctype.h>
  17 #include <unistd.h>
  18 #ifdef HAVE_SYS_TIME_H
  19 #include <sys/time.h>
  20 #endif
  21
  22 #include "debugfs.h"
  23 #include "ext2fs/kernel-jbd.h"
  24 #include "journal.h"
  25
  26 #undef DEBUG
  27
  28 #ifdef DEBUG
  29 # define dbg_printf(f, a...)  do {printf("JFS DEBUG: " f, ## a); \
  30         fflush(stdout); \
  31 } while (0)
  32 #else
  33 # define dbg_printf(f, a...)
  34 #endif
  35
  36 #define JOURNAL_CHECK_TRANS_MAGIC(x)    \
  37         do { \
  38                 if ((x)->magic != J_TRANS_MAGIC) \
  39                         return EXT2_ET_INVALID_ARGUMENT; \
  40         } while (0)
  41
  42 #define J_TRANS_MAGIC           0xD15EA5ED
  43 #define J_TRANS_OPEN            1
  44 #define J_TRANS_COMMITTED       2
  45 struct journal_transaction_s {
  46         unsigned int magic;
  47         ext2_filsys fs;
  48         journal_t *journal;
  49         blk64_t block;
  50         blk64_t start, end;
  51         tid_t tid;
  52         int flags;
  53 };
  54
  55 typedef struct journal_transaction_s journal_transaction_t;
  56
  57 static journal_t *current_journal = NULL;
  58
  59 static void journal_dump_trans(journal_transaction_t *trans EXT2FS_ATTR((unused)),
  60                                const char *tag EXT2FS_ATTR((unused)))
  61 {
  62         dbg_printf("TRANS %p(%s): tid=%d start=%llu block=%llu end=%llu "
  63                    "flags=0x%x\n", trans, tag, trans->tid, trans->start,
  64                    trans->block, trans->end, trans->flags);
  65 }
  66
  67 static errcode_t journal_commit_trans(journal_transaction_t *trans)
  68 {
  69         struct buffer_head *bh, *cbh = NULL;
  70         struct commit_header *commit;
  71 #ifdef HAVE_SYS_TIME_H
  72         struct timeval tv;
  73 #endif
  74         errcode_t err;
  75
  76         JOURNAL_CHECK_TRANS_MAGIC(trans);
  77
  78         if ((trans->flags & J_TRANS_COMMITTED) ||
  79             !(trans->flags & J_TRANS_OPEN))
  80                 return EXT2_ET_INVALID_ARGUMENT;
  81
  82         bh = getblk(trans->journal->j_dev, 0, trans->journal->j_blocksize);
  83         if (bh == NULL)
  84                 return ENOMEM;
  85
  86         /* write the descriptor block header */
  87         commit = (struct commit_header *)bh->b_data;
  88         commit->h_magic = ext2fs_cpu_to_be32(JFS_MAGIC_NUMBER);
  89         commit->h_blocktype = ext2fs_cpu_to_be32(JFS_COMMIT_BLOCK);
  90         commit->h_sequence = ext2fs_cpu_to_be32(trans->tid);
  91         if (jfs_has_feature_checksum(trans->journal)) {
  92                 __u32 csum_v1 = ~0;
  93                 blk64_t cblk;
  94
  95                 cbh = getblk(trans->journal->j_dev, 0,
  96                              trans->journal->j_blocksize);
  97                 if (cbh == NULL) {
  98                         err = ENOMEM;
  99                         goto error;
 100                 }
 101
 102                 for (cblk = trans->start; cblk < trans->block; cblk++) {
 103                         err = journal_bmap(trans->journal, cblk,
 104                                            &cbh->b_blocknr);
 105                         if (err)
 106                                 goto error;
 107                         mark_buffer_uptodate(cbh, 0);
 108                         ll_rw_block(READ, 1, &cbh);
 109                         err = cbh->b_err;
 110                         if (err)
 111                                 goto error;
 112                         csum_v1 = ext2fs_crc32_be(csum_v1,
 113                                         (unsigned char const *)cbh->b_data,
 114                                         cbh->b_size);
 115                 }
 116
 117                 commit->h_chksum_type = JFS_CRC32_CHKSUM;
 118                 commit->h_chksum_size = JFS_CRC32_CHKSUM_SIZE;
 119                 commit->h_chksum[0] = ext2fs_cpu_to_be32(csum_v1);
 120         } else {
 121                 commit->h_chksum_type = 0;
 122                 commit->h_chksum_size = 0;
 123                 commit->h_chksum[0] = 0;
 124         }
 125 #ifdef HAVE_SYS_TIME_H
 126         gettimeofday(&tv, NULL);
 127         commit->h_commit_sec = ext2fs_cpu_to_be32(tv.tv_sec);
 128         commit->h_commit_nsec = ext2fs_cpu_to_be32(tv.tv_usec * 1000);
 129 #else
 130         commit->h_commit_sec = 0;
 131         commit->h_commit_nsec = 0;
 132 #endif
 133
 134         /* Write block */
 135         jbd2_commit_block_csum_set(trans->journal, bh);
 136         err = journal_bmap(trans->journal, trans->block, &bh->b_blocknr);
 137         if (err)
 138                 goto error;
 139
 140         dbg_printf("Writing commit block at %llu:%llu\n", trans->block,
 141                    bh->b_blocknr);
 142         mark_buffer_dirty(bh);
 143         ll_rw_block(WRITE, 1, &bh);
 144         err = bh->b_err;
 145         if (err)
 146                 goto error;
 147         trans->flags |= J_TRANS_COMMITTED;
 148         trans->flags &= ~J_TRANS_OPEN;
 149         trans->block++;
 150
 151         ext2fs_set_feature_journal_needs_recovery(trans->fs->super);
 152         ext2fs_mark_super_dirty(trans->fs);
 153 error:
 154         if (cbh)
 155                 brelse(cbh);
 156         brelse(bh);
 157         return err;
 158 }
 159
 160 static errcode_t journal_add_revoke_to_trans(journal_transaction_t *trans,
 161                                              blk64_t *revoke_list,
 162                                              size_t revoke_len)
 163 {
 164         journal_revoke_header_t *jrb;
 165         void *buf;
 166         size_t i, offset;
 167         blk64_t curr_blk;
 168         unsigned int sz;
 169         unsigned csum_size = 0;
 170         struct buffer_head *bh;
 171         errcode_t err;
 172
 173         JOURNAL_CHECK_TRANS_MAGIC(trans);
 174
 175         if ((trans->flags & J_TRANS_COMMITTED) ||
 176             !(trans->flags & J_TRANS_OPEN))
 177                 return EXT2_ET_INVALID_ARGUMENT;
 178
 179         if (revoke_len == 0)
 180                 return 0;
 181
 182         /* Do we need to leave space at the end for a checksum? */
 183         if (journal_has_csum_v2or3(trans->journal))
 184                 csum_size = sizeof(struct journal_revoke_tail);
 185
 186         curr_blk = trans->block;
 187
 188         bh = getblk(trans->journal->j_dev, curr_blk,
 189                     trans->journal->j_blocksize);
 190         if (bh == NULL)
 191                 return ENOMEM;
 192         jrb = buf = bh->b_data;
 193         jrb->r_header.h_magic = ext2fs_cpu_to_be32(JFS_MAGIC_NUMBER);
 194         jrb->r_header.h_blocktype = ext2fs_cpu_to_be32(JFS_REVOKE_BLOCK);
 195         jrb->r_header.h_sequence = ext2fs_cpu_to_be32(trans->tid);
 196         offset = sizeof(*jrb);
 197
 198         if (jfs_has_feature_64bit(trans->journal))
 199                 sz = 8;
 200         else
 201                 sz = 4;
 202
 203         for (i = 0; i < revoke_len; i++) {
 204                 /* Block full, write to journal */
 205                 if (offset + sz > trans->journal->j_blocksize - csum_size) {
 206                         jrb->r_count = ext2fs_cpu_to_be32(offset);
 207                         jbd2_revoke_csum_set(trans->journal, bh);
 208
 209                         err = journal_bmap(trans->journal, curr_blk,
 210                                            &bh->b_blocknr);
 211                         if (err)
 212                                 goto error;
 213                         dbg_printf("Writing revoke block at %llu:%llu\n",
 214                                    curr_blk, bh->b_blocknr);
 215                         mark_buffer_dirty(bh);
 216                         ll_rw_block(WRITE, 1, &bh);
 217                         err = bh->b_err;
 218                         if (err)
 219                                 goto error;
 220
 221                         offset = sizeof(*jrb);
 222                         curr_blk++;
 223                 }
 224
 225                 if (revoke_list[i] >=
 226                     ext2fs_blocks_count(trans->journal->j_fs_dev->k_fs->super)) {
 227                         err = EXT2_ET_BAD_BLOCK_NUM;
 228                         goto error;
 229                 }
 230
 231                 if (jfs_has_feature_64bit(trans->journal))
 232                         *((__u64 *)(&((char *)buf)[offset])) =
 233                                 ext2fs_cpu_to_be64(revoke_list[i]);
 234                 else
 235                         *((__u32 *)(&((char *)buf)[offset])) =
 236                                 ext2fs_cpu_to_be32(revoke_list[i]);
 237                 offset += sz;
 238         }
 239
 240         if (offset > 0) {
 241                 jrb->r_count = ext2fs_cpu_to_be32(offset);
 242                 jbd2_revoke_csum_set(trans->journal, bh);
 243
 244                 err = journal_bmap(trans->journal, curr_blk, &bh->b_blocknr);
 245                 if (err)
 246                         goto error;
 247                 dbg_printf("Writing revoke block at %llu:%llu\n",
 248                            curr_blk, bh->b_blocknr);
 249                 mark_buffer_dirty(bh);
 250                 ll_rw_block(WRITE, 1, &bh);
 251                 err = bh->b_err;
 252                 if (err)
 253                         goto error;
 254                 curr_blk++;
 255         }
 256
 257 error:
 258         trans->block = curr_blk;
 259         brelse(bh);
 260         return err;
 261 }
 262
 263 static errcode_t journal_add_blocks_to_trans(journal_transaction_t *trans,
 264                                       blk64_t *block_list, size_t block_len,
 265                                       FILE *fp)
 266 {
 267         blk64_t curr_blk, jdb_blk;
 268         size_t i, j;
 269         int csum_size = 0;
 270         journal_header_t *jdb;
 271         journal_block_tag_t *jdbt;
 272         int tag_bytes;
 273         void *buf = NULL, *jdb_buf = NULL;
 274         struct buffer_head *bh = NULL, *data_bh;
 275         errcode_t err;
 276
 277         JOURNAL_CHECK_TRANS_MAGIC(trans);
 278
 279         if ((trans->flags & J_TRANS_COMMITTED) ||
 280             !(trans->flags & J_TRANS_OPEN))
 281                 return EXT2_ET_INVALID_ARGUMENT;
 282
 283         if (block_len == 0)
 284                 return 0;
 285
 286         /* Do we need to leave space at the end for a checksum? */
 287         if (journal_has_csum_v2or3(trans->journal))
 288                 csum_size = sizeof(struct journal_block_tail);
 289
 290         curr_blk = jdb_blk = trans->block;
 291
 292         data_bh = getblk(trans->journal->j_dev, curr_blk,
 293                          trans->journal->j_blocksize);
 294         if (data_bh == NULL)
 295                 return ENOMEM;
 296         buf = data_bh->b_data;
 297
 298         /* write the descriptor block header */
 299         bh = getblk(trans->journal->j_dev, curr_blk,
 300                     trans->journal->j_blocksize);
 301         if (bh == NULL) {
 302                 err = ENOMEM;
 303                 goto error;
 304         }
 305         jdb = jdb_buf = bh->b_data;
 306         jdb->h_magic = ext2fs_cpu_to_be32(JFS_MAGIC_NUMBER);
 307         jdb->h_blocktype = ext2fs_cpu_to_be32(JFS_DESCRIPTOR_BLOCK);
 308         jdb->h_sequence = ext2fs_cpu_to_be32(trans->tid);
 309         jdbt = (journal_block_tag_t *)(jdb + 1);
 310
 311         curr_blk++;
 312         for (i = 0; i < block_len; i++) {
 313                 j = fread(data_bh->b_data, trans->journal->j_blocksize, 1, fp);
 314                 if (j != 1) {
 315                         err = errno;
 316                         goto error;
 317                 }
 318
 319                 tag_bytes = journal_tag_bytes(trans->journal);
 320
 321                 /* No space left in descriptor block, write it out */
 322                 if ((char *)jdbt + tag_bytes >
 323                     (char *)jdb_buf + trans->journal->j_blocksize - csum_size) {
 324                         jbd2_descr_block_csum_set(trans->journal, bh);
 325                         err = journal_bmap(trans->journal, jdb_blk,
 326                                            &bh->b_blocknr);
 327                         if (err)
 328                                 goto error;
 329                         dbg_printf("Writing descriptor block at %llu:%llu\n",
 330                                    jdb_blk, bh->b_blocknr);
 331                         mark_buffer_dirty(bh);
 332                         ll_rw_block(WRITE, 1, &bh);
 333                         err = bh->b_err;
 334                         if (err)
 335                                 goto error;
 336
 337                         jdbt = (journal_block_tag_t *)(jdb + 1);
 338                         jdb_blk = curr_blk;
 339                         curr_blk++;
 340                 }
 341
 342                 if (block_list[i] >=
 343                     ext2fs_blocks_count(trans->journal->j_fs_dev->k_fs->super)) {
 344                         err = EXT2_ET_BAD_BLOCK_NUM;
 345                         goto error;
 346                 }
 347
 348                 /* Fill out the block tag */
 349                 jdbt->t_blocknr = ext2fs_cpu_to_be32(block_list[i] & 0xFFFFFFFF);
 350                 jdbt->t_flags = 0;
 351                 if (jdbt != (journal_block_tag_t *)(jdb + 1))
 352                         jdbt->t_flags |= ext2fs_cpu_to_be16(JFS_FLAG_SAME_UUID);
 353                 else {
 354                         memcpy(jdbt + tag_bytes,
 355                                trans->journal->j_superblock->s_uuid,
 356                                sizeof(trans->journal->j_superblock->s_uuid));
 357                         tag_bytes += 16;
 358                 }
 359                 if (i == block_len - 1)
 360                         jdbt->t_flags |= ext2fs_cpu_to_be16(JFS_FLAG_LAST_TAG);
 361                 if (*((__u32 *)buf) == ext2fs_cpu_to_be32(JFS_MAGIC_NUMBER)) {
 362                         *((__u32 *)buf) = 0;
 363                         jdbt->t_flags |= ext2fs_cpu_to_be16(JFS_FLAG_ESCAPE);
 364                 }
 365                 if (jfs_has_feature_64bit(trans->journal))
 366                         jdbt->t_blocknr_high = ext2fs_cpu_to_be32(block_list[i] >> 32);
 367                 jbd2_block_tag_csum_set(trans->journal, jdbt, data_bh,
 368                                         trans->tid);
 369
 370                 /* Write the data block */
 371                 err = journal_bmap(trans->journal, curr_blk,
 372                                    &data_bh->b_blocknr);
 373                 if (err)
 374                         goto error;
 375                 dbg_printf("Writing data block %llu at %llu:%llu tag %d\n",
 376                            block_list[i], curr_blk, data_bh->b_blocknr,
 377                            tag_bytes);
 378                 mark_buffer_dirty(data_bh);
 379                 ll_rw_block(WRITE, 1, &data_bh);
 380                 err = data_bh->b_err;
 381                 if (err)
 382                         goto error;
 383
 384                 curr_blk++;
 385                 jdbt = (journal_block_tag_t *)(((char *)jdbt) + tag_bytes);
 386         }
 387
 388         /* Write out the last descriptor block */
 389         if (jdbt != (journal_block_tag_t *)(jdb + 1)) {
 390                 jbd2_descr_block_csum_set(trans->journal, bh);
 391                 err = journal_bmap(trans->journal, jdb_blk, &bh->b_blocknr);
 392                 if (err)
 393                         goto error;
 394                 dbg_printf("Writing descriptor block at %llu:%llu\n",
 395                            jdb_blk, bh->b_blocknr);
 396                 mark_buffer_dirty(bh);
 397                 ll_rw_block(WRITE, 1, &bh);
 398                 err = bh->b_err;
 399                 if (err)
 400                         goto error;
 401         }
 402
 403 error:
 404         trans->block = curr_blk;
 405         if (bh)
 406                 brelse(bh);
 407         brelse(data_bh);
 408         return err;
 409 }
 410
 411 static blk64_t journal_guess_blocks(journal_t *journal, blk64_t data_blocks,
 412                                     blk64_t revoke_blocks)
 413 {
 414         blk64_t ret = 1;
 415         unsigned int bs, sz;
 416
 417         /* Estimate # of revoke blocks */
 418         bs = journal->j_blocksize;
 419         if (journal_has_csum_v2or3(journal))
 420                 bs -= sizeof(struct journal_revoke_tail);
 421         sz = jfs_has_feature_64bit(journal) ? sizeof(__u64) : sizeof(__u32);
 422         ret += revoke_blocks * sz / bs;
 423
 424         /* Estimate # of data blocks */
 425         bs = journal->j_blocksize - 16;
 426         if (journal_has_csum_v2or3(journal))
 427                 bs -= sizeof(struct journal_block_tail);
 428         sz = journal_tag_bytes(journal);
 429         ret += data_blocks * sz / bs;
 430
 431         ret += data_blocks;
 432
 433         return ret;
 434 }
 435
 436 static errcode_t journal_open_trans(journal_t *journal,
 437                                     journal_transaction_t *trans,
 438                                     blk64_t blocks)
 439 {
 440         trans->fs = journal->j_fs_dev->k_fs;
 441         trans->journal = journal;
 442         trans->flags = J_TRANS_OPEN;
 443
 444         if (journal->j_tail == 0) {
 445                 /* Clean journal, start at the tail */
 446                 trans->tid = journal->j_tail_sequence;
 447                 trans->start = journal->j_first;
 448         } else {
 449                 /* Put new transaction at the head of the list */
 450                 trans->tid = journal->j_transaction_sequence;
 451                 trans->start = journal->j_head;
 452         }
 453
 454         trans->block = trans->start;
 455         if (trans->start + blocks > journal->j_last)
 456                 return ENOSPC;
 457         trans->end = trans->block + blocks;
 458         journal_dump_trans(trans, "new transaction");
 459
 460         trans->magic = J_TRANS_MAGIC;
 461         return 0;
 462 }
 463
 464 static errcode_t journal_close_trans(journal_transaction_t *trans)
 465 {
 466         journal_t *journal;
 467
 468         JOURNAL_CHECK_TRANS_MAGIC(trans);
 469
 470         if (!(trans->flags & J_TRANS_COMMITTED))
 471                 return 0;
 472
 473         journal = trans->journal;
 474         if (journal->j_tail == 0) {
 475                 /* Update the tail */
 476                 journal->j_tail_sequence = trans->tid;
 477                 journal->j_tail = trans->start;
 478                 journal->j_superblock->s_start = ext2fs_cpu_to_be32(trans->start);
 479         }
 480
 481         /* Update the head */
 482         journal->j_head = trans->end + 1;
 483         journal->j_transaction_sequence = trans->tid + 1;
 484
 485         trans->magic = 0;
 486
 487         /* Mark ourselves as needing recovery */
 488         if (!ext2fs_has_feature_journal_needs_recovery(trans->fs->super)) {
 489                 ext2fs_set_feature_journal_needs_recovery(trans->fs->super);
 490                 ext2fs_mark_super_dirty(trans->fs);
 491         }
 492
 493         return 0;
 494 }
 495
 496 #define JOURNAL_WRITE_NO_COMMIT         1
 497 static errcode_t journal_write(journal_t *journal,
 498                                int flags, blk64_t *block_list,
 499                                size_t block_len, blk64_t *revoke_list,
 500                                size_t revoke_len, FILE *fp)
 501 {
 502         blk64_t blocks;
 503         journal_transaction_t trans;
 504         errcode_t err;
 505
 506         if (revoke_len > 0) {
 507                 jfs_set_feature_revoke(journal);
 508                 mark_buffer_dirty(journal->j_sb_buffer);
 509         }
 510
 511         blocks = journal_guess_blocks(journal, block_len, revoke_len);
 512         err = journal_open_trans(journal, &trans, blocks);
 513         if (err)
 514                 goto error;
 515
 516         err = journal_add_blocks_to_trans(&trans, block_list, block_len, fp);
 517         if (err)
 518                 goto error;
 519
 520         err = journal_add_revoke_to_trans(&trans, revoke_list, revoke_len);
 521         if (err)
 522                 goto error;
 523
 524         if (!(flags & JOURNAL_WRITE_NO_COMMIT)) {
 525                 err = journal_commit_trans(&trans);
 526                 if (err)
 527                         goto error;
 528         }
 529
 530         err = journal_close_trans(&trans);
 531         if (err)
 532                 goto error;
 533 error:
 534         return err;
 535 }
 536
 537 void do_journal_write(int argc, char *argv[])
 538 {
 539         blk64_t *blist = NULL, *rlist = NULL;
 540         size_t bn = 0, rn = 0;
 541         FILE *fp = NULL;
 542         int opt;
 543         int flags = 0;
 544         errcode_t err;
 545
 546         if (current_journal == NULL) {
 547                 printf("Journal not open.\n");
 548                 return;
 549         }
 550
 551         reset_getopt();
 552         while ((opt = getopt(argc, argv, "b:r:c")) != -1) {
 553                 switch (opt) {
 554                 case 'b':
 555                         err = read_list(optarg, &blist, &bn);
 556                         if (err)
 557                                 com_err(argv[0], err,
 558                                         "while reading block list");
 559                         break;
 560                 case 'r':
 561                         err = read_list(optarg, &rlist, &rn);
 562                         if (err)
 563                                 com_err(argv[0], err,
 564                                         "while reading revoke list");
 565                         break;
 566                 case 'c':
 567                         flags |= JOURNAL_WRITE_NO_COMMIT;
 568                         break;
 569                 default:
 570                         printf("%s [-b blocks] [-r revoke] [-c] file\n",
 571                                argv[0]);
 572                         printf("-b: Write these blocks into transaction.\n");
 573                         printf("-c: Do not commit transaction.\n");
 574                         printf("-r: Revoke these blocks from transaction.\n");
 575
 576                         goto out;
 577                 }
 578         }
 579
 580         if (bn > 0 && optind != argc - 1) {
 581                 printf("Need a file to read blocks from.\n");
 582                 return;
 583         }
 584
 585         if (bn > 0) {
 586                 fp = fopen(argv[optind], "r");
 587                 if (fp == NULL) {
 588                         com_err(argv[0], errno,
 589                                 "while opening journal data file");
 590                         goto out;
 591                 }
 592         }
 593
 594         err = journal_write(current_journal, flags, blist, bn,
 595                             rlist, rn, fp);
 596         if (err)
 597                 com_err("journal_write", err, "while writing journal");
 598
 599         if (fp)
 600                 fclose(fp);
 601 out:
 602         if (blist)
 603                 free(blist);
 604         if (rlist)
 605                 free(rlist);
 606 }
 607
 608 /* Make sure we wrap around the log correctly! */
 609 #define wrap(journal, var)                                              \
 610 do {                                                                    \
 611         if (var >= (journal)->j_last)                                   \
 612                 var -= ((journal)->j_last - (journal)->j_first);        \
 613 } while (0)
 614
 615 /*
 616  * Count the number of in-use tags in a journal descriptor block.
 617  */
 618
 619 static int count_tags(journal_t *journal, char *buf)
 620 {
 621         char                    *tagp;
 622         journal_block_tag_t     *tag;
 623         int                     nr = 0, size = journal->j_blocksize;
 624         int                     tag_bytes = journal_tag_bytes(journal);
 625
 626         if (journal_has_csum_v2or3(journal))
 627                 size -= sizeof(struct journal_block_tail);
 628
 629         tagp = buf + sizeof(journal_header_t);
 630
 631         while ((tagp - buf + tag_bytes) <= size) {
 632                 tag = (journal_block_tag_t *) tagp;
 633
 634                 nr++;
 635                 tagp += tag_bytes;
 636                 if (!(tag->t_flags & ext2fs_cpu_to_be16(JFS_FLAG_SAME_UUID)))
 637                         tagp += 16;
 638
 639                 if (tag->t_flags & ext2fs_cpu_to_be16(JFS_FLAG_LAST_TAG))
 640                         break;
 641         }
 642
 643         return nr;
 644 }
 645
 646 static errcode_t journal_find_head(journal_t *journal)
 647 {
 648         unsigned int            next_commit_ID;
 649         blk64_t                 next_log_block, head_block;
 650         int                     err;
 651         journal_superblock_t    *sb;
 652         journal_header_t        *tmp;
 653         struct buffer_head      *bh;
 654         unsigned int            sequence;
 655         int                     blocktype;
 656
 657         /*
 658          * First thing is to establish what we expect to find in the log
 659          * (in terms of transaction IDs), and where (in terms of log
 660          * block offsets): query the superblock.
 661          */
 662
 663         sb = journal->j_superblock;
 664         next_commit_ID = ext2fs_be32_to_cpu(sb->s_sequence);
 665         next_log_block = ext2fs_be32_to_cpu(sb->s_start);
 666         head_block = next_log_block;
 667
 668         if (next_log_block == 0)
 669                 return 0;
 670
 671         bh = getblk(journal->j_dev, 0, journal->j_blocksize);
 672         if (bh == NULL)
 673                 return ENOMEM;
 674
 675         /*
 676          * Now we walk through the log, transaction by transaction,
 677          * making sure that each transaction has a commit block in the
 678          * expected place.  Each complete transaction gets replayed back
 679          * into the main filesystem.
 680          */
 681         while (1) {
 682                 dbg_printf("Scanning for sequence ID %u at %lu/%lu\n",
 683                           next_commit_ID, (unsigned long)next_log_block,
 684                           journal->j_last);
 685
 686                 /* Skip over each chunk of the transaction looking
 687                  * either the next descriptor block or the final commit
 688                  * record. */
 689                 err = journal_bmap(journal, next_log_block, &bh->b_blocknr);
 690                 if (err)
 691                         goto err;
 692                 mark_buffer_uptodate(bh, 0);
 693                 ll_rw_block(READ, 1, &bh);
 694                 err = bh->b_err;
 695                 if (err)
 696                         goto err;
 697
 698                 next_log_block++;
 699                 wrap(journal, next_log_block);
 700
 701                 /* What kind of buffer is it?
 702                  *
 703                  * If it is a descriptor block, check that it has the
 704                  * expected sequence number.  Otherwise, we're all done
 705                  * here. */
 706
 707                 tmp = (journal_header_t *)bh->b_data;
 708
 709                 if (tmp->h_magic != ext2fs_cpu_to_be32(JFS_MAGIC_NUMBER)) {
 710                         dbg_printf("JBD2: wrong magic 0x%x\n", tmp->h_magic);
 711                         goto err;
 712                 }
 713
 714                 blocktype = ext2fs_be32_to_cpu(tmp->h_blocktype);
 715                 sequence = ext2fs_be32_to_cpu(tmp->h_sequence);
 716                 dbg_printf("Found magic %d, sequence %d\n",
 717                           blocktype, sequence);
 718
 719                 if (sequence != next_commit_ID) {
 720                         dbg_printf("JBD2: Wrong sequence %d (wanted %d)\n",
 721                                    sequence, next_commit_ID);
 722                         goto err;
 723                 }
 724
 725                 /* OK, we have a valid descriptor block which matches
 726                  * all of the sequence number checks.  What are we going
 727                  * to do with it?  That depends on the pass... */
 728
 729                 switch (blocktype) {
 730                 case JFS_DESCRIPTOR_BLOCK:
 731                         next_log_block += count_tags(journal, bh->b_data);
 732                         wrap(journal, next_log_block);
 733                         continue;
 734
 735                 case JFS_COMMIT_BLOCK:
 736                         head_block = next_log_block;
 737                         next_commit_ID++;
 738                         continue;
 739
 740                 case JFS_REVOKE_BLOCK:
 741                         continue;
 742
 743                 default:
 744                         dbg_printf("Unrecognised magic %d, end of scan.\n",
 745                                   blocktype);
 746                         err = -EINVAL;
 747                         goto err;
 748                 }
 749         }
 750
 751 err:
 752         if (err == 0) {
 753                 dbg_printf("head seq=%d blk=%llu\n", next_commit_ID,
 754                            head_block);
 755                 journal->j_transaction_sequence = next_commit_ID;
 756                 journal->j_head = head_block;
 757         }
 758         brelse(bh);
 759         return err;
 760 }
 761
 762 static void update_journal_csum(journal_t *journal, int ver)
 763 {
 764         journal_superblock_t *jsb;
 765
 766         if (journal->j_format_version < 2)
 767                 return;
 768
 769         if (journal->j_tail != 0 ||
 770             ext2fs_has_feature_journal_needs_recovery(
 771                                         journal->j_fs_dev->k_fs->super)) {
 772                 printf("Journal needs recovery, will not add csums.\n");
 773                 return;
 774         }
 775
 776         /* metadata_csum implies journal csum v3 */
 777         jsb = journal->j_superblock;
 778         if (ext2fs_has_feature_metadata_csum(journal->j_fs_dev->k_fs->super)) {
 779                 printf("Setting csum v%d\n", ver);
 780                 switch (ver) {
 781                 case 2:
 782                         jfs_clear_feature_csum3(journal);
 783                         jfs_set_feature_csum2(journal);
 784                         jfs_clear_feature_checksum(journal);
 785                         break;
 786                 case 3:
 787                         jfs_set_feature_csum3(journal);
 788                         jfs_clear_feature_csum2(journal);
 789                         jfs_clear_feature_checksum(journal);
 790                         break;
 791                 default:
 792                         printf("Unknown checksum v%d\n", ver);
 793                         break;
 794                 }
 795                 journal->j_superblock->s_checksum_type = JBD2_CRC32C_CHKSUM;
 796                 journal->j_csum_seed = jbd2_chksum(journal, ~0, jsb->s_uuid,
 797                                                    sizeof(jsb->s_uuid));
 798         } else {
 799                 jfs_clear_feature_csum3(journal);
 800                 jfs_clear_feature_csum2(journal);
 801                 jfs_set_feature_checksum(journal);
 802         }
 803 }
 804
 805 static void update_uuid(journal_t *journal)
 806 {
 807         size_t z;
 808         ext2_filsys fs;
 809
 810         if (journal->j_format_version < 2)
 811                 return;
 812
 813         for (z = 0; z < sizeof(journal->j_superblock->s_uuid); z++)
 814                 if (journal->j_superblock->s_uuid[z])
 815                         break;
 816         if (z == 0)
 817                 return;
 818
 819         fs = journal->j_fs_dev->k_fs;
 820         if (!ext2fs_has_feature_64bit(fs->super))
 821                 return;
 822
 823         if (jfs_has_feature_64bit(journal) &&
 824             ext2fs_has_feature_64bit(fs->super))
 825                 return;
 826
 827         if (journal->j_tail != 0 ||
 828             ext2fs_has_feature_journal_needs_recovery(fs->super)) {
 829                 printf("Journal needs recovery, will not set 64bit.\n");
 830                 return;
 831         }
 832
 833         memcpy(journal->j_superblock->s_uuid, fs->super->s_uuid,
 834                sizeof(fs->super->s_uuid));
 835 }
 836
 837 static void update_64bit_flag(journal_t *journal)
 838 {
 839         if (journal->j_format_version < 2)
 840                 return;
 841
 842         if (!ext2fs_has_feature_64bit(journal->j_fs_dev->k_fs->super))
 843                 return;
 844
 845         if (jfs_has_feature_64bit(journal) &&
 846             ext2fs_has_feature_64bit(journal->j_fs_dev->k_fs->super))
 847                 return;
 848
 849         if (journal->j_tail != 0 ||
 850             ext2fs_has_feature_journal_needs_recovery(
 851                                 journal->j_fs_dev->k_fs->super)) {
 852                 printf("Journal needs recovery, will not set 64bit.\n");
 853                 return;
 854         }
 855
 856         jfs_set_feature_64bit(journal);
 857 }
 858
 859 void do_journal_open(int argc, char *argv[])
 860 {
 861         int opt, enable_csum = 0, csum_ver = 3;
 862         journal_t *journal;
 863         errcode_t err;
 864
 865         if (check_fs_open(argv[0]))
 866                 return;
 867         if (check_fs_read_write(argv[0]))
 868                 return;
 869         if (check_fs_bitmaps(argv[0]))
 870                 return;
 871         if (current_journal) {
 872                 printf("Journal is already open.\n");
 873                 return;
 874         }
 875         if (!ext2fs_has_feature_journal(current_fs->super)) {
 876                 printf("Journalling is not enabled on this filesystem.\n");
 877                 return;
 878         }
 879
 880         reset_getopt();
 881         while ((opt = getopt(argc, argv, "cv:f:")) != -1) {
 882                 switch (opt) {
 883                 case 'c':
 884                         enable_csum = 1;
 885                         break;
 886                 case 'f':
 887                         if (current_fs->journal_name)
 888                                 free(current_fs->journal_name);
 889                         current_fs->journal_name = strdup(optarg);
 890                         break;
 891                 case 'v':
 892                         csum_ver = atoi(optarg);
 893                         if (csum_ver != 2 && csum_ver != 3) {
 894                                 printf("Unknown journal csum v%d\n", csum_ver);
 895                                 csum_ver = 3;
 896                         }
 897                         break;
 898                 default:
 899                         printf("%s: [-c] [-v ver] [-f ext_jnl]\n", argv[0]);
 900                         printf("-c: Enable journal checksumming.\n");
 901                         printf("-v: Use this version checksum format.\n");
 902                         printf("-f: Load this external journal.\n");
 903                 }
 904         }
 905
 906         err = ext2fs_open_journal(current_fs, &current_journal);
 907         if (err) {
 908                 com_err(argv[0], err, "while opening journal");
 909                 return;
 910         }
 911         journal = current_journal;
 912
 913         dbg_printf("JOURNAL: seq=%d tailseq=%d start=%lu first=%lu "
 914                    "maxlen=%lu\n", journal->j_tail_sequence,
 915                    journal->j_transaction_sequence, journal->j_tail,
 916                    journal->j_first, journal->j_last);
 917
 918         update_uuid(journal);
 919         update_64bit_flag(journal);
 920         if (enable_csum)
 921                 update_journal_csum(journal, csum_ver);
 922
 923         err = journal_find_head(journal);
 924         if (err)
 925                 com_err(argv[0], err, "while examining journal");
 926 }
 927
 928 void do_journal_close(int argc EXT2FS_ATTR((unused)),
 929                       char *argv[] EXT2FS_ATTR((unused)))
 930 {
 931         if (current_journal == NULL) {
 932                 printf("Journal not open.\n");
 933                 return;
 934         }
 935
 936         ext2fs_close_journal(current_fs, &current_journal);
 937 }
 938
 939 void do_journal_run(int argc EXT2FS_ATTR((unused)), char *argv[])
 940 {
 941         errcode_t err;
 942
 943         if (check_fs_open(argv[0]))
 944                 return;
 945         if (check_fs_read_write(argv[0]))
 946                 return;
 947         if (check_fs_bitmaps(argv[0]))
 948                 return;
 949         if (current_journal) {
 950                 printf("Please close the journal before recovering it.\n");
 951                 return;
 952         }
 953
 954         err = ext2fs_run_ext3_journal(&current_fs);
 955         if (err)
 956                 com_err("journal_run", err, "while recovering journal");
 957         else {
 958                 ext2fs_clear_feature_journal_needs_recovery(current_fs->super);
 959                 ext2fs_mark_super_dirty(current_fs);
 960         }
 961 }